The hunt continues, I've been looking for something very similar, trying to keep a fleet of only boost sized wheels and hubs for the fleet.
Too bad about the Trifox, the price sure is right and it'd otherwise make a good base for a bikepacking rig.

I ended up getting one of the original eeSilk seatposts (not the eeSilk+) for ~$48usd recently:
https://www.aliexpress.com/item/1005006004691351.html

I compared it really closely to the photos on Cane Creek's website, and while it's missing the Cane Creek branding on the seatpost itself, it does have the logo on the elastomer part, and says 'eeSilk' on the side.

As far as I can tell it's an exact copy of the now discontinued 'base model' aluminum version: https://www.canecreek.com/products/eesilk

Have about 300km of use on it, and I love it so far, zero noise, zero creaks - it just works.  Weighs exactly what the original says it does in the marketing materials.

Apparently once upon a time these shipped with 3 different elastomers so you could tune the ride yourself, although Cane Creek's own website says in some places that the additional elastomers only come with the carbon version.

One thing even the alloy version is supposed to come with (but the AliExpress copy didn't) was the special rebuild tool you're supposed to use to drive the axles out and back in for lubrication and servicing.  I'm fairly certain I can bodge a way to sort that out on my own when the time comes, though.=